Substrate drying method and substrate processing apparatus

Abstract

An upper surface of a substrate is supplied with a pre-drying processing liquid which is a solution of a sublimable substance and a solvent. Thereafter, the solvent is evaporated from the pre-drying processing liquid on the substrate and a solid of the sublimable substance is precipitated in the pre-drying processing liquid on the substrate. Thereafter, at least a portion of the solid of the sublimable substance is dissolved in the pre-drying processing liquid on the substrate. Thereafter, the solvent is evaporated from the pre-drying processing liquid in which the solid of the sublimable substance has been dissolved and the solid of the sublimable substance is precipitated onto the substrate. Thereafter, the solid of the sublimable substance is sublimated and removed from the upper surface of the substrate.

What is claimed is: 
     
       1. A substrate drying method comprising:
 a pre-drying processing liquid supplying step of supplying an upper surface of a substrate, on which a pattern is formed, with a pre-drying processing liquid which is a solution including a sublimable substance corresponding to a solute and a solvent in which the sublimable substance dissolved, and forming a liquid film of the pre-drying processing liquid onto the upper surface of the substrate; 
 a first precipitation step of precipitating a solid of the sublimable substance in the pre-drying processing liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid on the upper surface of the substrate; 
 a first dissolving step of dissolving at least a portion of the solid of the sublimable substance in the pre-drying processing liquid on the upper surface of the substrate; 
 a final precipitation step of precipitating the solid of the sublimable substance onto the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid in which the solid of the sublimable substance has been dissolved; and 
 a sublimating step of removing the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance. 
 
     
     
       2. The substrate drying method according to  claim 1 , wherein
 the first precipitation step includes a room temperature precipitation step of precipitating the solid of the sublimable substance onto the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid on the upper surface of the substrate while keeping a temperature of the pre-drying processing liquid on the upper surface of the substrate lower than or equal to a room temperature. 
 
     
     
       3. The substrate drying method according to  claim 1 , wherein
 the first dissolving step includes a heating step of heating the pre-drying processing liquid on the upper surface of the substrate at a heating temperature higher than a room temperature. 
 
     
     
       4. The substrate drying method according to  claim 3 , wherein
 the heating step includes an indirectly heating step of heating the pre-drying processing liquid on the upper surface of the substrate at the heating temperature by heating the substrate from below the substrate. 
 
     
     
       5. The substrate drying method according to  claim 3 , wherein
 the final precipitation step includes a step of precipitating the solid of the sublimable substance onto the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid on the upper surface of the substrate while heating the pre-drying processing liquid on the upper surface of the substrate at the heating temperature. 
 
     
     
       6. The substrate drying method according to  claim 1 , wherein
 the first precipitation step includes a liquid surface precipitation step of precipitating the solid of the sublimable substance onto a surface of the pre-drying processing liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid on the upper surface of the substrate, 
 the first dissolving step includes a spontaneously dissolving step of allowing at least a portion of the solid of the sublimable substance to dissolve in or be dissolved in the pre-drying processing liquid on the upper surface of the substrate by allowing the temperature of the pre-drying processing liquid to increase or be increased due to heat of an atmosphere in contact with the solid of the sublimable substance. 
 
     
     
       7. A substrate processing apparatus comprising:
 a pre-drying processing liquid supplying unit that supplies an upper surface of a substrate, on which a pattern is formed, with a pre-drying processing liquid which is a solution including a sublimable substance corresponding to a solute and a solvent in which the sublimable substance dissolved, and forms a liquid film of the pre-drying processing liquid onto the upper surface of the substrate; 
 a first precipitation unit that precipitates a solid of the sublimable substance in the pre-drying processing liquid on the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid on the upper surface of the substrate; 
 a first dissolving unit that dissolves at least a portion of the solid of the sublimable substance in the pre-drying processing liquid on the upper surface of the substrate; 
 a final precipitation unit that precipitates the solid of the sublimable substance onto the upper surface of the substrate by evaporating the solvent from the pre-drying processing liquid in which the solid of the sublimable substance has been dissolved; and 
 a sublimating unit that removes the solid of the sublimable substance from the upper surface of the substrate by sublimating the solid of the sublimable substance.